Briton to Pilot First Commercial Space Flights
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case One, well you do seem to be very self opinionated for someone aged only five! I don't think risk taking just for the fun of it can be classed as bravery. Bravery is something our boys and girls out in Afganistan are demonstrating every day, It's not something being demonstrated by a bunch of rich kids booking flights on Galactica!
Last edited by BALLSOUT; 20th Aug 2011 at 11:48.
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However, Kostenko says he hopes that the station can be a stopover for manned circumlunar flights, so making day trips to the far side of the moon and back may be a day-trip option.
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ap08, we're not talking about "massive" radiation exposure. The highest exposure on an apollo mission was just under 3 Rem - about the same as a pilot will experience in ten years.
So it's a relatively high dose of radiation, but not massive. If my memory is correct then the risk of getting cancer would be increased by no more than 0.4% as a result of that amount of radiation.
So it's a relatively high dose of radiation, but not massive. If my memory is correct then the risk of getting cancer would be increased by no more than 0.4% as a result of that amount of radiation.
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There are some problems with this 3 Rem number:
1. Rem is not the best unit to measure the effects of radiation exposure. The effect on the human body depends not just on the dose, but also on the type of radiation absorbed. During lunar missions, the astronaut is exposed to an unusual type of radiation - extremely energetic particles from outside the solar system, whose biological effect is not well known, because the only way to get exposed to such radiation on earth is to put your head in a particle accelerator. There are reports of flashes seen by astronauts with their eyes closed, the cause of such flashes is unknown but the most probable cause are those high energy cosmic rays. Radiation that is able to create flashes in your eyes, can't be good for your health...
2. The exact exposure is not predictable. An unexpected spike in solar activity can increase the exposure many times. If there were just a few Apollo missions and they reached 3 Rem - it is reasonable to assume that during hundreds or thousands of missions, the maximum exposure will be several times higher.
3. The effect of "small" radiation doses is the subject of debate. No one can say for certain that a certain dose is "safe".
EDIT: here is some evidence that the Apollo missions were not harmless for the astronauts health...
"At least 39 former astronauts have suffered some form of cataracts after flying in space, according to a 2001 study by Francis Cucinotta of NASA's Johnson Space Center (see journal references below). Of those 39 astronauts, 36 had flown on high-radiation missions such as the Apollo Moon landings. Some cataracts appeared as soon as 4 or 5 years after the mission, but others took 10 or more years to manifest."
Blinding Flashes - NASA Science
1. Rem is not the best unit to measure the effects of radiation exposure. The effect on the human body depends not just on the dose, but also on the type of radiation absorbed. During lunar missions, the astronaut is exposed to an unusual type of radiation - extremely energetic particles from outside the solar system, whose biological effect is not well known, because the only way to get exposed to such radiation on earth is to put your head in a particle accelerator. There are reports of flashes seen by astronauts with their eyes closed, the cause of such flashes is unknown but the most probable cause are those high energy cosmic rays. Radiation that is able to create flashes in your eyes, can't be good for your health...
2. The exact exposure is not predictable. An unexpected spike in solar activity can increase the exposure many times. If there were just a few Apollo missions and they reached 3 Rem - it is reasonable to assume that during hundreds or thousands of missions, the maximum exposure will be several times higher.
3. The effect of "small" radiation doses is the subject of debate. No one can say for certain that a certain dose is "safe".
EDIT: here is some evidence that the Apollo missions were not harmless for the astronauts health...
"At least 39 former astronauts have suffered some form of cataracts after flying in space, according to a 2001 study by Francis Cucinotta of NASA's Johnson Space Center (see journal references below). Of those 39 astronauts, 36 had flown on high-radiation missions such as the Apollo Moon landings. Some cataracts appeared as soon as 4 or 5 years after the mission, but others took 10 or more years to manifest."
Blinding Flashes - NASA Science
Last edited by ap08; 20th Aug 2011 at 18:07.
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I don't get that "feather" mode though
The tail "feathering" has been a standard feature of free-flight model airplanes for decades, usually set off by a fused hold-down that burns through after a certain amount of time, to prevent the model from flying beyond a recoverable distance.
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Does anyone seriously think that the risk of cancer is even close to the risk of getting killed by the flight itself?
I very much doubt whether typical personal life insurance policies (which exclude "hazardous activities") would count this as anything but "hazardous".
I can also imagine, in the event of loss of the aircraft, some shareholders of the companies run by the wealthy individuals who will be on board, asking some questions about the company's risk policy.
I very much doubt whether typical personal life insurance policies (which exclude "hazardous activities") would count this as anything but "hazardous".
I can also imagine, in the event of loss of the aircraft, some shareholders of the companies run by the wealthy individuals who will be on board, asking some questions about the company's risk policy.
What surprises me is the velocities projected on that flight profile diagram posted above. Running mach 4 at various altitudes between 20 and 50 kilometers through an online atmospheric properties calculator, it appears that some parts of the vehicle skin may be exposed to total air temperatures exceeding 700 degrees C. Not your typical Long-EZ!
Edited to add that: Even if the ship is accelerated to mach 4 while level at 50,000' then zoom climbed to apogee, total air temp still exceeds 600 C.
Edited to add that: Even if the ship is accelerated to mach 4 while level at 50,000' then zoom climbed to apogee, total air temp still exceeds 600 C.
Last edited by westhawk; 21st Aug 2011 at 09:23. Reason: Additional info
Does the craft have any form of reacrion controls, oris the whole thing ballistic once the conventional controls don't work?
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ap08, the radiation discussion is tangential - if you want to continue it then jetblast is probably the place to do so.
For the original spaceshipone the max velocity (about 960m/s) was at burnout, altitude about 55km. Peak heating was a little lower and the max temperature was just over 600C.
Because it doesn't go much out of the atmosphere the conventional controls should be functional for most of the flight. It wil lhave a reaction control system fitted, though.
What surprises me is the velocities projected on that flight profile diagram posted above. Running mach 4 at various altitudes between 20 and 50 kilometers through an online atmospheric properties calculator, it appears that some parts of the vehicle skin may be exposed to total air temperatures exceeding 700 degrees C. Not your typical Long-EZ!
Does the craft have any form of reacrion controls, oris the whole thing ballistic once the conventional controls don't work?
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Virgin's passenger spaceship completes first rocket test flight
Virgin's passenger spaceship completes first rocket test flight | Reuters
A six-passenger spaceship owned by an offshoot of Virgin Group fired its rocket engine in flight for the first time on Monday, a key step toward the start of commercial service in about a year, Virgin owner Richard Branson said.
The powered test flight over California's Mojave Desert lasted 16 seconds and broke the sound barrier.
"It was stunning," Branson told Reuters. "You could see it very, very clearly. Putting the rocket and the spaceship together and seeing it perform safely, it was a critical day."
The powered test flight over California's Mojave Desert lasted 16 seconds and broke the sound barrier.
"It was stunning," Branson told Reuters. "You could see it very, very clearly. Putting the rocket and the spaceship together and seeing it perform safely, it was a critical day."
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Hate to divert the thread on a slight tangent however I have a question regarding the operation of a commercial flight within the US? Which I think this is.
If so will US DOT procedures apply?
Thinking back to the Virgin America debacle it doesn't appear that Virgin Galactic qualifies to operate commerical flights in the US because its ownership is not by "US citizens":
VG appears to be a wholly owned subsiderary of Virgin Group.
If so will US DOT procedures apply?
Thinking back to the Virgin America debacle it doesn't appear that Virgin Galactic qualifies to operate commerical flights in the US because its ownership is not by "US citizens":
(A) An individual who is a citizen of the United States; (B) A partnership each of whose partners is an individual who is a citizen of the United States; or (C) A corporation or association organized under the laws of the United States or a State, the District of Columbia, or a territory or possession of the United States, of which the president and at least two-thirds of the board of directors and other managing officers are citizens of the United States, which is under the actual control of citizens of the United States, and in which at least 75 percent of the voting interest is owned or controlled by persons that are citizens of the United States.
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David Mackay does indeed seem to be highly qualified for this job. However, I have never heard his name in gliding circles.
I'm sure some gliding would be useful. He will need to get the landing right first time in SS2! My old gliding clubs at Tibenham or Cambridge might oblige. You never know, they might give him a free course - that would be wonderful publicity for the club concerned.
I'm sure some gliding would be useful. He will need to get the landing right first time in SS2! My old gliding clubs at Tibenham or Cambridge might oblige. You never know, they might give him a free course - that would be wonderful publicity for the club concerned.
Last edited by jackharr; 2nd May 2013 at 09:16.
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I don't know what all the fuss is about...after all, it's hardly rocket science is it?
....oh wait....
....oh wait....
Rocket engineering on the other hand.... that can be tricky.
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Originally Posted by jackharr
David Mackay does indeed seem to be highly qualified for this job. However, I have never heard his name in gliding circles.
I'm sure some gliding would be useful.
He will need to get the landing right first time in SS2!
My old gliding clubs at Tibenham or Cambridge might oblige. You never know, they might give him a free course - that would be wonderful publicity for the club concerned.
Sorry Jack.
Do a Hover - it avoids G
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Sorry if it upsets any gliding fans but what SS2 requires at the end of each flight is nothing that is even vaguely related to the sport of gliding.
Many moons ago I did some low L/D operations as well as enjoyed a Discus (for example). The Discus needed some thought, aptitude and currency to be operated well (and what a delight it was). But low L/D is a totally different kettle of fish. It is actually easier to land from a glide angle of some 45deg and with a speed of 250kts that the Discus ever will be.
Why so? Because when you are pointing down at the ground at 45deg and a stabilised 250kt your impact point becomes pretty clear. So all you have to do is adjust the impact point to the beginning of the lead in lights, pull out of the dive at low level and drift down the lead in lights while the speed bleeds back and land on the numbers at 150-170 kt. No skill. Don’t worry about the wind either.
To the onlookers the pilot who keeps doing this spot landing day after day appears to be some sort of flying god. He is nothing of the sort because it is so easy.
To practice this sort of approach using a Hunter I liked 10,000 ft in the vicinity of the downwind leg, then with gear down and full flap dive at the flap limit of 250ft as described above. Absolute doddle.
Mind you getting the SS2 to the start of such a circuit is something else again – and also has nothing to do with the sport of gliding.
Many moons ago I did some low L/D operations as well as enjoyed a Discus (for example). The Discus needed some thought, aptitude and currency to be operated well (and what a delight it was). But low L/D is a totally different kettle of fish. It is actually easier to land from a glide angle of some 45deg and with a speed of 250kts that the Discus ever will be.
Why so? Because when you are pointing down at the ground at 45deg and a stabilised 250kt your impact point becomes pretty clear. So all you have to do is adjust the impact point to the beginning of the lead in lights, pull out of the dive at low level and drift down the lead in lights while the speed bleeds back and land on the numbers at 150-170 kt. No skill. Don’t worry about the wind either.
To the onlookers the pilot who keeps doing this spot landing day after day appears to be some sort of flying god. He is nothing of the sort because it is so easy.
To practice this sort of approach using a Hunter I liked 10,000 ft in the vicinity of the downwind leg, then with gear down and full flap dive at the flap limit of 250ft as described above. Absolute doddle.
Mind you getting the SS2 to the start of such a circuit is something else again – and also has nothing to do with the sport of gliding.
